Just a quick question - why aren't you carrying the required mats to make a portal whenever you are exploring?
I always take mats for a portal, workbench and when playing vanilla a storage box. Building a small base at the edge is fine but it means you have to return to it every night to head back to home base, cutting down your exploration time.
With the portal and workbench mats on you just keep exploring until just before night then put up a portal, store portal restricted items in storage box and go home. When your inventory is full or you're close to being encumbered head back to your boat or build that portal and transport non-restricted items back to home base.
Stuff that you build won't get attacked if you're not in the vicinity so it's safe to leave it there overnight or for several days if needed. If you're in a crypt and have built this stuff on the ground then it might get attacked as the game considers you in the vicinity. The crypt roof is safe from attacks.